The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the inventors hereof, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
The present disclosure relates to disk memory systems. Disk memory systems typically contain a disk on which information (usually in the form of digital data) can be recorded (written) and/or from which recorded information can be retrieved (read).
In systems of a type mentioned above, the information is generally recorded in a plurality of concentric circular paths or tracks on the disk. The “head” that writes data to and/or reads data from the disk must follow particular ones of these tracks in order to write data to or read data from the disk.
In order to read desired information from the disk, the read head must be properly located “over” a track containing that desired information. To facilitate such read head positioning, the disk is also recorded with several radially extending and angularly spaced “wedges” of information that contain track-identifying information, and also information that can be used to control a read-head-positioning mechanism to optimally center the read head over a desired track, especially in a direction that is radial of the disk.
Only some of the above-mentioned wedges may be so-called “full servo wedges.” A full servo wedge includes a full complement of information such as track and sector identifying information for each track, as well as so-called “servo” information for helping the read-head-positioning mechanism to radially position the head over the desired track. Such full servo wedges may be angularly interspersed (or inter-digitated) with so-called “short servo wedges.” A short servo wedge may contain only servo information for helping to ensure that the read head remains radially centered over the track it is already currently reading data from.
The present disclosure relates to improving the performance of disk memory systems that employ short servo wedges.